This proposal is designed to examine the question of whether changes can be brought about in the cellular lipids and fatty acid metabolism of leukocytes as a result of alterations of the fatty acid concentration and composition of their extracellular environment. The phospholipids of the cell membranes would be of special interest, since changes in them might result in variation in membrane transport of antineoplastic drugs. The rates of fatty acid utilization will be examined with labeled fatty acids, and the lipid composition will be determined using thin-layer and gas-liquid chromatography. The hypothesis will be examined in two systems: 1) Leukocytes obtained from normal human volunteers fed either a high saturated or polyunsaturated fat diet and 2) L1210 mouse leukemia cells from animals fed either a high saturated or polyunsaturated fat diet. In the animal model, the median survival of animals carrying the L1210 leukemia and receiving concurrent antineoplastic drugs will be compared for those animals receiving either a high saturated or polyunsaturated fat diet.